/***************************************************************************
 *   Copyright (C) 2007 by Kai Winter   *
 *   kaiwinter@gmx.de   *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#ifndef IMAGEMANAGER_H
#define IMAGEMANAGER_H

#include <QObject>
#include <QPixmapCache>
#include <QDebug>
#include <QMutex>
#include <QBuffer>
#include "mapnetwork.h"

namespace qmapcontrol
{
	class MapNetwork;
	/**
	@author Kai Winter <kaiwinter@gmx.de>
	 */
	class ImageManager : public QObject
	{
		Q_OBJECT;
		public:
			static ImageManager* instance()
			{
				if(!m_Instance)
				{
					m_Instance = new ImageManager;
				}
				return m_Instance;
			}
		
			~ImageManager();

		//! returns a QPixmap of the asked image
		/*!
			 * If this component doesn´t have the image a network query gets started to load it.
			 * @param host the host of the image
			 * @param path the path to the image
			 * @return the pixmap of the asked image
		 */
			QPixmap getImage(const QString& host, const QString& path);
		
			QPixmap prefetchImage(const QString& host, const QString& path);
		
			void receivedImage(const QPixmap pixmap, const QString& url);
		
		/*!
			 * This method is called by MapNetwork, after all images in its queue were loaded.
			 * The ImageManager emits a signal, which is used in MapControl to remove the zoom image.
			 * The zoom image should be removed on Tile Images with transparency.
			 * Else the zoom image stay visible behind the newly loaded tiles.
		 */
			void loadingQueueEmpty();
		
		/*!
			 * Aborts all current loading threads.
			 * This is useful when changing the zoom-factor, though newly needed images loads faster
		 */
			void abortLoading();
		
		//! sets the proxy for HTTP connections
		/*!
			 * This method sets the proxy for HTTP connections.
			 * This is not provided by the current Qtopia version!
			 * @param host the proxy´s hostname or ip
			 * @param port the proxy´s port
		 */
			void setProxy(QString host, int port);

		private:
			ImageManager(QObject* parent = 0);
			ImageManager(const ImageManager&);
			ImageManager& operator=(const ImageManager&);
			QPixmap emptyPixmap;
			MapNetwork* net;
			QVector<QString> prefetch;
	
			static ImageManager* m_Instance;

            bool saveTile(QString,QPixmap );
            bool loadTile(QString,QPixmap &);
            bool tileExist(QString);
		
		signals:
			void imageReceived();
			void loadingFinished();
	};
}
#endif
